LEPIDOPTERA

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singly on the food-plant. The larvae are usually bare, and are
slightly thickened in the centre. The prothorax is constricted,
which gives the caterpillar the appearance of having a neck.
The larvae of this family make much greater use of silk than
do other Rhopalocem, and frequently spin leaves together for
concealment. The pupa is elongated, with a spine at the
posterior end of the body, and is, in most cases, enclosed in a
rudimentary cocoon composed of a folded leaf.

Hibernation occurs in all stages: in Britain the Skippers
hibernate as eggs or larvae.

In some cases the sexes can be distinguished by the presence
in the male of an oblique band of black scales on the fore-wing;
in many cases, however, sex recognition is difficult.

Hesperiids are of slight economic importance. One species,
Parnara (Chapra) mathias attacks rice in India, while others,
of which Hesperia conjuncta from Java will serve as an example,
cause injury to the foliage of sugar cane.

Sub-Order II. HETEROCERA. Moths
Antennae of many diverse forms, but not clubbed ;
frenulum usually present. Heterocera are not, as a rule,
day-flying, and generally pupate in a cocoon.
The characters of the Heterocera are not well defined, and
the group is not a natural one. It was formerly divided into
two series, macro- and micro-lepidoptera ; although this was
convenient, it had no scientific justification, and this method
of classification has been abandoned, though the term " micro-
lepidoptera " is still frequently used as a comprehensive name
for the smaller moths. It has been proposed to form a separate
sub-order of the two families Hepialidce and Micropterygidce,
but these families agree only in the primitive character of the
wings, and differ widely in many other important points.
The moths are usually easily distinguished from Rhopalocera,
their bodies are stouter, their antennae are not clubbed, and
the wings are not held vertically above the body when at rest.
The majority of moths fly in the dusk of the evening, and their
coloration is, as a rule, less brilliant than that of the butterflies.
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